This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Glucose metabolism in cats under a variety of dietary conditions is being analyzed as part of a study of obesity. By following isotope labels (carbon-13 and deuterium) and measuring amounts of label at specific atom sites in glucose, one can evaluate different metabolic pathways. The analysis involves preparing and extracting a glucose derivative (1,2-isopropylidene-glucofuranose or 'monoacetone glucose') from plasma, collecting carbon-13 and deuterium NMR spectra of this compound, and measuring relative peak intensities. The data are then analyzed according to published algorithms to identify the source of each atom. The collaborative work includes modifying sample preparation and NMR data acquisition protocols in order to increase overall signal sensitivity, due to the lower amounts of plasma and isotope enrichment available in the cat samples relative to published work on rats and humans. In addition to the medically relevant data, this project will be a test application of analytical NMR.